Superheater.



"0. $35.48!. Patented Oct. 24, I899. G. HENKEL.

SUPEBHEATER.

Amman and m 11, 1898.)

(No Model.)

W; mess as mdfvfe m iTED GUSTAV I-IENKEL, OF XVILHELMSHOHE, GERMANY.

SUPERH EATER.

SPECIFIGATIQN formingoart of Letters Patent No. 635,481, dated October24, 1899. Application filed July 11, 1898. Serial No. 685,675. (Nomodel.)

To aZZ whom it may concern:

Beit known that I, GUSTAV HENKEL, a subject of the King of Prussia,German Emperor,

and a resident of Wilhelmshohe, near Cassel,

in the Province of Hesse-NassamGerman Empire, have invented certain newand useful Improvements in Superheaters with Regulable AdjustableGrates, (for which patent application was filed in Germany on the 13thof December, 1897, and in Sweden on the 13th of December, 1897,) ofwhich the following is an exact specification.

This invention relates to superheaters with regulable adjustable grates,and has for its object to provide for the arrangement of a superheater,more especially where a very limited space for such purpose isavailable.

The invention described hereinafter 'permits of the employment of asuperheating device in the smallest possible occupation of space or thesmallest imaginable heating-surface of the heating-body and providesalso for the attainment of a high superheating of the steam. By theemployment of a superheater of this description the possibility ofobtaining a superheating of the steam is afforded also for such boilerswhere only a very limited space for the building in of the superheaterinthe region of the fire-box is available. As, however, the attaining ofsuch object is only possible by the influence of the most intensiveaction of the tire upon the heating-surface of the superheater-that isto say, at a position of the superheater where the same is in closestproximity to the fire it becomes a necessity to maintain the durabilityof the superheater that the same during the first firing-up of theboiler or during pauses in the use of the steam plant, that the saidsuperheater may be so arranged that the same shall be protected from theextreme heat of the fire, more especially from the socalled pointed ordirect flame, and in general that the capability of the regulation ofthe heat toward the superheater shall be as nearly perfect as it ispossible to attain.

The above-sketched problem has been solved in the manner hereinafterdescribed, and shown in the drawings forming part of this specification,in which- Figures 1 and 2 show a circular superheater constructedaccording to my invention in vertical section and plan, while Figs. 3and t sl1ow a slightly-modified shape of a supercould be substituted bychannels inside the said cast-steelor cast-iron ring, the said channelsbeing formed to a superheater without employing the previouslymentionedwroughtiron spiral; but in this latter case a risk of a loss of steamwould exist not only by the possible presence of small pores and cracksin such superheating body, but also by the diffusion or expansion of atemporary but very high degree of heat exercised upon the superheater.There are also, as will be apparent, technical difficulties in theproper construction of channels of so small a size as would be necessaryfor such superheating bodies. On the other hand, it could not also beseriously taken into consideration to construct uncovered spirals, moreespecially with refere nce to the question of their durability, norwould it be practicable to expose the bare tube-spiral to the action ofthe direct flame. For this reason a fireproof material such as isafforded, for instance, by wrought-iron, is absolutely necessary for theprotection of the spiral. Furthermore, it is also apparent that thegreater mass of metal (when using the Wrought-iron mantle or body) willalso tend to protect the superheater from the great variation of theheat caused by the unequal stoking of the fire. Thus the metal mass inwhich the spiral is embedded forms to a certain degree a kind ofheat-accumulator.

In order to prevent too excessive an action of the fire upon thesuperheateri. 6., to optionally regulate this action or infiuence thegrate is provided with a device which by means of a simple handmanipulation per-' mits the adjusting of the grate at any height withinthe ring a. When the boiler is first fired up or stoked, the grate wouldbe so placed that its top edge or its upper edge would approximatelyclose,as it were,the ring (1, whereby, as is apparent, the said ring awould be absolutelyprotected from the pointed or direct flame. \Vhen forthe purpose of starting the engine the steam-valveis opened, so that thering receives the necessary cooling by the flow of steam into thespiral, the grate should be allowed to sink and subsequently lifted orraised, as required, when the temperature of the steam again becomes toogreat. The closed position of the ring must be assumed at acomparatively low height in order that when the grate is in its lowestposition the attention to the same may not be made too inconvenient.

If the superheater is so arranged as represented by Figs. 3 and 4viz.,that instead of the same being entirely of a closed shape the latter isopen at the front (resembling in form that of a reap-hook)-the resultwould be: First, the height would then not be dependent upon theposition of the fire-doors; second, there would be convenient space toconduct the flow and return pipes from underneath and yet have the samefully protected, (see Fig. 3,) while when the ring is closed or when thesuperheater has an entirely circular shape the conducting of the waterwould have to be efiectcd through a horizontal tube 1), Fig. 1, where itwas desired to avoid the attachment of a projection. extending towardthe inside, which would have the effect of decreasing the size of thegrate.

The before mentioned closed circularshaped superheater possesses theadvantage that the tube cast in can consist of a continuous spiral,while, as shown in Fig. 3, in the case of the open or reap-hook-shapedsuperheater it would be necessary to employ connectors or caps for thetubes of the return flow. Notwithstanding the above for existingboilers, however, this lastnamed construction would be chosen, moreespecially on account of the possibility of the convenient building inof the same. In general it Although this last-described superheate-r isin an especial degree suitable for the last-named type of boilers, yetthe use of the same would be practicable as an example for fire-tubeboilers, for which cases the superheating-frame would be given a U shapeand would be open toward the fire-door.

Lastly the device for raising and lowering the grate could of course beeffected by various mechanisms. Care only must be taken that themovement is such as to avoid any binding which could be occasioned byonesided pressure and friction upon the grate or uponthesuperheating-frame. Furthermore,

the mechanism chosen must not allow the grate to move in a slantingdirection; also the actuating mechanism here in question must beexceedingly simple and must not render the grate nor the ash-boxinaccessible for cleaning purposes. These conditions I have fulfilled bymeans of the lever construction described, and shown in Figs. 1 and 2.This mechanism is as follows: Two short shafts c c with four levers (Zgrip the grate-frame at four points simultaneously and raise and lowerthe same without any lateral pressure when the hand lever is actuated,said handlever e by means of the diagonal rodfand lever connecting thetwo shafts e and c. As the two levers (Z d, or, more precisely, each setof levers d (1, move in an opposite direction, all lateral pressure isremoved, in consequence of which the grate is lifted in afreely-suspended condition.

Having thus fully described the nature of this invention, what I desireto secure by Letters Patent of the United States is- In a steamsuperheating device, in which the superheater proper can itself beheated by the flames of a furnace, the combination with a circularsuper-heater having its super heating-pipes inclosed in a vertical wall,a vertically-movable grate surrounded by said superheating-pipes, meansfor displacing the grate and maintaining it at any height to protect thesuperheater against the pointingflame while stoking the boiler,substantially as set forth.

In witness whereof I have hereunto set my hand in presence of twoWitnesses.

GUSTAV HENKEL.

Witnesses:

JULIUS FRANKIE, LULU KoTHE.

